Among the basic processes of processing silver halide color photographic material that are effected after exposure of the photographic material to a light image, are those of color developing, silver bleaching, silver halide fixing, bleaching fixing, in which a bleaching process and a fixing process are effected at a time, water washing, rinsing which is effected in lieu of the water washing process, stabilizing and drying. In addition, there are additional processes, which are executed to permit each process solution to be used stably or to increase the physical strength and stability of the processed photographic material.
Among methods of processing silver halide color photographic materials are those of processing color negative films to obtain color prints, which are the methods most widely used today, and those for directly obtaining final images in the form of positive color films or prints. Further, users of color prints want to see the prints as soon as possible and desire the production of prints in as short a period of time as possible. To meet this demand, it is necessary to provide quick processing.
In recent years, it is possible to quickly process silver halide color photographic materials owing to improvements therein. In addition, easy processing of a large quantity of materials is possible with automatic developing apparatus. Further, the automatic developing apparatus has been improved, and a variety of compact and inexpensive apparatuses have been developed. Today, numerous such automatic developing apparatuses are used. In order to obtain a large quantity of photographs easily and quickly, an automatic developing apparatus is normally used for carrying out the above photographic process. In actual processing of a large quantity of photographic materials, the process of a given quantity of photographic material is carried out while replenishing with a necessary quantity of process solution as replenishment solution. A photographic material processor who accepts a request to process photographic material from a photographer has to effect the desired process in a short period of time.
In order to process a silver halide color photographic material easily and quickly, agents necessary for the processing are available on the market in the form of a liquid so that they can be used as processing solutions by simply diluting with water. Processing of a silver halide color photographic material comprises various processes, including color developing, silver bleaching, silver halide fixing, water washing, rinsing, stabilizing and so forth, and some of these processing steps are divided into a plurality of parts, for which numerous solution parts have to be supplied. The most important step in processing a silver halide color photographic material is color developing, wherein a color developing agent oxidized by a silver halide that has been exposed to light reacts with coupler contained in the photographic material, thereby generating a pigment image. Color developer solution supplied for this step is normally separated in three or more parts. The reason for this separation into a plurality of parts is to prevent the quality of the developer from deteriorating even in cases where there may be a long interval between the time the developer was produced and actually used and also to ensure that composition of each solution part is such that it does not present any problem when mixed with other solutions.
In actual practice, color developer solution is supplied separately in three or more parts, which includes a part containing a paraphenylene diamine type color developing agent to be oxidized by silver halide exposed to light and then, reacting with coupler contained in the photographic material, generate a pigment image; a part containing a hydroxylamine type compound to improve stability of the color developer solution; and a part or parts containing a substance to keep the color developer solution alkaline and any other necessary substances. Among these parts, if supplied as a liquid, a paraphenylene diamine type color developing agent has to be stable even when subjected to various storage conditions. As a paraphenylene diamine type color developing agent tends to be oxidized in storage, it is normally prepared as aqueous solution with sulfurous compound being added to prevent oxidation of the agent. Examples of methods for improving stability of compositions of color developing agents supplied in the form of aqueous solution are shown in Japanese Patent Publication No. 37957/1970, like Publication No. 24050/1973, Japanese Patent Application Public Disclosure No. 136045/1988, like Disclosure No. 181245/1993 and U.S. Pat. Nos. 3,615,572, 3,647,461 and 3,647,462. All of the aforementioned, however, call for using sulfurous acid and therefore present a problem in that sulfur dioxide is generated. If supplied as liquid, a hydroxylamine type compound, too, has to be stable even when subjected to various storage conditions. Therefore, it is supplied in the form of aqueous solution which is solely comprised of the hydroxylamine type compound and water.
As described above, in conventional practice, color developer solution used for processing silver halide color photographic material is supplied separately in three or more solution parts in order to maintain the quality of each respective composition. In other words, only the present invention has succeeded in providing the compositions that constitute color developer solution in two solution parts by combining a paraphenylene diamine type color developing agent and a hydroxylamine type compound into a single solution part. The present invention is also the first to provide a paraphenylene diamine type color developing agent and a hydroxylamine type compound in a solid state, which the present invention offers hereby.
As color developer solution used for processing silver halide color photographic material is the key composition in photographic processing and its stability is especially important, the solution is conventionally provided in a plurality of solution parts (parts) in order to increase the stability in storage. The processing thus requires numerous solution parts (parts), resulting in inconvenient handling as well as an increased quantity of waste after use. Therefore, there is a demand for a color developing agent composition which is convenient to handle, produces less waste after use and has superior stability in storage.
In order to provide a color developing agent composition which is convenient to handle, produces less waste after use and has superior stability in storage, the inventors conducted research and investigations concerning the way to supply compositions that constitute color developer solution in two parts or two solution parts, and, as a result, found that the above objective could be attained by a paraphenylene diamine type color developing agent which contains a particular compound and a hydroxylamine type compound which also contains a particular compound. The present invention is predicated in this finding.